1. Modify install.xml to install the Selva theme. Sloan theme is still the
default theme when .LRN is installed, but you can now use the site template
admin pages to make selva your theme.
2. Hid Kelp theme from view. It's still installed as a portal theme, but if
you want to make it visible to the site template stuff you need to add
it via the "add site template" web UI page.